Is my roof too small for solar panels, what to do?

Reed_Richards

I'm not sure that unit costs tell you much that is meaningful, because they depend too much on the usage pattern of the individual. In August my unit cost was 6.33p per kWh. But the vast majority of the electricity I use at this time of year is on charging my EV and heating my hot water. I can do both of those at the ultra-cheap night rate of my EV tariff; that rate will more than double when it expires in December. Not only that but I have solar panels and a battery and they deal with the majority of my daytime consumption. So just at the moment I am doing very well; come January things will be different.

QrizB

My unit cost on Agile is about 16p over the last 3 months.

That's an interesting chart. Do you know how many of those 1988 kWh were used for EV charging and how many were general household use? From the look of the chart, maybe ~900 kWh for the EV and ~1100 kWh for everything else?

For example, if a 12+ kWh battery that would cover the majority of your daytime use, you could then switch to Octopus Go and buy almost all your electricity for 9.5p/kWh. You might get your average cost down to 12p/kWh or less. A saving of £80-£100 every quarter, if that chart is typical.

This company for example is quoting £4300 for a 5kW Solis inverter plus a 16kWh Fogstar battery, installed.

Edit: even with the above I'd suggest getting a quote to fit whatever solar PV is possible on your roof. You might only fit 3-4 panels, 1.5-2kW, but provided the cost isn't disproportionate those will give you useful daytime power outside of the Octopus Go (or EON Next Drive, or Economy 7) night-time off-peak periods.

Uncle_Cuddles

Would the new Ecoflow 5000 stream be suitable as a starter battery? Around £1500 for 5kWh, small and expandable.

QrizB

Would the new Ecoflow 5000 stream be suitable as a starter battery? Around £1500 for 5kWh, small and expandable.

As plug-in batteries aren't yet approved, if you want a "legal" system you'll have to get an electrician to install it.

And if you're going to do that, there are other options around that price point.

I'm not saying Ecoflow is a bad choice, but it's worth looking at the other options from eg. Anker, Fogstar and Sunsynk. Fogstar and Sunsynk in perticular use "standard" 48 volt batteries for expansion and so will be cheaper if you decide to add more capacity in future.

Uncle_Cuddles

https://forums.moneysavingexpert.com/discussion/comment/82136244#Comment_82136244

So for example this is available on preorder for a few hundred more with 3 times the capacity. Can this just be installed as is or do I need to also buy an inverter, or is that only required if i have solar too?

Fogstar link

QrizB

^ That's just a battery, useless to you without an inverter.

Fogstar's battery-and-inverter bundles are here:

https://www.fogstar.co.uk/collections/battery-inverter-bundle